The 40 year Senden leads by one over his fellow US based Queenslander Jason Day who is aiming for his first professional win in Australia and his first Australian Open title in his debut in the event as a professional.
One shot further back is the 1998 winner, Greg Chalmers while Nick O'Hern and Nick Watney both produced strong finishing bursts to move to 9 under and they sit within just three shots of the lead.
O'Hern eagled the 17th and then holed a lengthy putt across the last to give himself a chance of adding the Australian open to his Australian PGA Championship title.
36 hole leader Tiger Woods was a surprise today given the quality of his play on the opening two days but given what we have seen today then he is perhaps not yet completely out of things.
Woods dropped three shots in his opening three holes and although he birdied the 4th hole he never really recovered and finished with a round of 75 to be at 6 under and six from the lead.
Today gave an indication however of the volatility in scoring that The Lakes layout offers. There are plenty of birdie opportunities but there are also plenty of accidents waiting to happen. Throw in the fact that the Australian Open title is on the line then tomorrow's promises high drama.
Senden began solidly although his first birdie did not come until the 5th. Then things began to heat up. From 102 metres Senden holed his second shot at the par four 6th.
"That shot put me in a nice frame of mind heading into the back nine," said Senden after his round. "I think this golf course allows you to shape a lot of shots into the pins. It is a good fit and suits my eye."
A birdie at the 9th moved him to 7 under but the back nine would yield five more birdies including one at the last from 30 feet.
Senden has come off a very solid season in the US, a runner up finish at the BMW Championship in Chicago behind Justin Rose earning him a place amongst the elite field at the Tour Championship.
Senden was perhaps a little unlucky not to have earned his way into the Presidents Cup side but the battle for what appeared to be the one final position in Greg Norman's team came down to what was effectively a playoff at the Tour Championship. If Senden had have been able to repeat his effort in Chicago it might well have been him and not Baddeley with the final berth for Royal Melbourne.
It was not to be but with earnings of US$2.3 million it was nonetheless a very strong season and a year that might get a whole lot better tomorrow.
So where does today's round rate? "I still think the 65 at Royal Sydney was probably one of my favourite rounds," he added referring to the finishing burst that gave him his first national open.
Senden puts much of his improved play down to work he has been doing with his coach Ian Triggs at the Brookwater Golf club in Brisbane on speeding up his short game pre shot routine allowing a greater freedom.
"I have always felt with my long game I was pretty efficient. With my short game I was getting bogged down. We needed to match every single part of the game, chipping, putting, long game, in regards to keeping the same speed.
"I think that is important. With my driver I look out and let it go. I probably was not doing that for years with my putting. It is that inner belief to score. I tried to help myself with that. I think that the less time I take the information hits me better and try to feel that it is natural."
"I'd be lying if I said I wouldn't be nervous," added Senden responding to a question as to how he will feel tomorrow. "I think every player gets nervous about how you deal with it. I think it is about being in the moment, playing golf shots one at a time and doing the best you can with your mental work and routine. Have fun and enjoy it rather than make it stressful. That is all I can hope for tomorrow."
Jason Day turned 24 today and he could not have wished for a more significant birthday present than to be in a strong position to win his own national open. It might just be that an even greater present lies in wait tomorrow night.
In order for him to do so he will need to need to get past his fellow Queenslander and hold at bay a host of others who closed the gap on the leaders today.
In just his second professional event in Australia and his first appearance as a professional in his national open Day looked rock solid early on in his round before the first birdie came at the 5th.
It would be his second to the 8th hole however that would not only consolidate the lead he had gained two holes earlier but highlight the amazing talent that is Jason Day. Even with the wind into his face and from a slightly hanging lie, the temptation was too great from Day not to take on the par five. Out came the driver and with a shot that hardly ever left the stick he finished 40 feet behind the hole.
That it was that far from the hole hardly did justice to the shot. It was yet another example of Day's capacity to hit imaginative shots under the gun. He was unable to hole the lengthy eagle putt but did add another birdie and at the very next he made up for it with a 50 foot birdie putt across the green to turn in 32 and at 10 under had the lead by two.
His only hiccup came at the par 15th when he pulled his tee shot just a fraction and he was unable to get up and down from the left hand greenside bunker. "I was a little disappointed that I made the bogey on the 15th but I lost a little bit of focus when I hit that 4 iron into the water at the 14th but overall I am very happy with where I am."
14 players sit within seven shots of the lead and, as we discovered today, that sort of gap can be made up on this golf course with another round similar to that of John Senden's.